Studying Antarctica's Marine Organisms

Donal Manahan

Donal is a marine biologist who is interested in animal physiology. He explores how animals live and thrive at very cold temperatures, particularly in the early stages of life. In his spare time, he likes to study the early stages of Antarctic exploration! Donal has a real interest in the early explorers and the history of Antarctica.

AMNH: Why should kids know about Antarctica?

Donal: Kids should know about Antarctica because it's one of the most extreme continent on this planet, with 70% of the world's fresh water, and because the ozone depletion is there. The Antarctic is like the canary in the coal mine: if we keep a watchful eye on it, we'll know if things such as global warming and climate are changing everywhere."

AMNH: How can students everywhere be good stewards of our least known continent?

Donal: Be careful about what you put into the environment and the ocean. Be a careful, educated consumer. We all need to question where the food we eat comes from. Perhaps it could be a school project to ask your local store, or restaurants such as McDonalds, if they are selling Antarctic fish. Active consumers can make a difference. For example, "dolphin-free tuna" happened because people spoke up."

More on Donal Manahan the Person

Field of Study Marine Biology Hometown Dublin, Ireland Favorite Middle/High School Subjects Science was the "least painful." Least Favorite Middle/High School Subjects English Composition Thoughts on Middle/High School "I hated English Composition. My parents got so frustrated with me, just staring at a blank page, unable to come up with an idea. It would take me half a day to write something. Now it's my bread and butter. I have to write up papers about all of my work." Interests in Middle/High School Snorkeling off the coast. "There are wonderful lush kelp forests in the Irish sea, and I loved to fool around exploring them with my friends." Interests Today "If you find a job that's interesting, then your profession becomes your hobby. Even in my time off I like to do things related to my work. I also enjoy playing the guitar, camping, boating, and scuba diving." Life Lessons from the Field "You need discipline... in your training and meeting deadlines and doing things that you don't necessarily enjoy in order to get to do the exciting parts of the job." Major Influences "My uncle encouraged me to take a job doing something that interested me, or even volunteer for free, rather than trying to make money. That was the best advice, to find something that excites you and do that. It will help you much more than making an extra dollar." Number of Trips to Antarctica So Far Ten

AMNH: What's so important about your field of study in Antarctica?

Donal: Seventy percent of all marine mammals go though some type of larval stage. It is important for us to understand their complex life cycles so we can find out how their populations reproduce and how they live. Without accurate information about fish reproduction cycles and diet, we could remove a vital component of the food chain, or wipe out an entire fish population. This is vital for the fishing industry. We study animals to understand how they have adapted to the conditions of Antarctic waters. We work with sea urchins and sea stars because they produce lots of eggs. It's a mystery to us how these baby urchins and sea stars survive in such cold conditions, with so little food, and limited sunlight.

AMNH: If you're working with eggs and babies, you must need to get to Antarctica earlier in the season than most researchers do.

Donal: That's right. We usually go during Winter in August, to get everything set up. The trigger for the animals is the Sun coming up in August. We punch a hole in the sea ice and construct a hut over it to keep it warm In September, scuba divers go about six to eight feet below the surface, under the cover of sea ice, to collect the animals from the sea floor when they are ready to spawn. I used to dive myself, but don't anymore.

AMNH: Wow. What's the water like under the ice?

Donal: It's the clearest water on Earth, which is important biologically. It's so clear because there's not a lot of particulate material in the water, which means that the food concentration in the water is very low. Then there's a big seasonal burst in summer, and that's when the Antarctic organisms all have to get their energy. Antarctic animals have to solve the problem of surviving until food shows up. It's like parents having to tell their young, "We're not going to be able to feed you until Christmas, so hold your breath." We're not used to thinking about how early systems like that work.

AMNH: You said you can get alot of eggs from sea urchins and sea stars. How many is alot?

Donal: Half a million to one million for one female. If those are fertilized with one sperm, you've got one million brothers and sisters. That's why sea urchins have been so important in marine or medical research. You can control the genetics to a certain degree, and study the biochemistry at different stages of development. It's so interesting–we always think we need to keep babies well-nourished and warm. It may be true for humans, but these young grow up in the cold, dark waters. It's really interesting to study their metabolism.

AMNH: Do the animals actually spawn in the lab?

Donal: When we get them to the lab, we have to inject chemicals into the organisms when they are ripe; this induces them to spawn and release eggs. This doesn't harm the animals.

AMNH: What are you finding out in your research about these organisms?

Donal: We measure the animals' development over time. We monitor their metabolic rate–how fast they process calories–and we conduct other biochemical analyses to understand how they process energy so slowly. This helps us understand more about human obesity. Urchins and sea stars are metabolically very efficient; a very small amount of energy from the fats and proteins stored in the egg keeps the embryos alive. But there are some trade-offs to this life strategy. Because they're so efficient at using energy, they cannot grow very fast, even later in the season when they've developed into the larvae stage and much more food is available.

AMNH: Can commercial fishing work for organims that grow so slowly?

Donal: Now that the northern waters are getting depleted, fishing's moving to Antarctica. A lot of fisheries are going after deep-sea species like the orange roughie and Chilean sea bass. Because deep-sea fish and cold-water fish have a slower metabolism and longer life spans, these waters contain fewer, longer-lived species. There's evidence now that orange roughies live for many years and don't reproduce until they're thirty years old. If you deplete fish populations before they reach reproductive age, it has a really drastic effect. Organizations are trying very hard to stop overfishing. A lot of the problem is illegal fishing, which is very hard to stop, especially down there. There's no coast guard to patrol. I haven't seen that many fishing boats, but I go in on the McMurdo side. There's a lot of fishing on the other side. Right now fisheries are pushing hard to get fisheries in Antarctica.

AMNH: Maybe your work will help people make informed decisions. Is your work back home very different from what you do in Antarctica?

Donal: We bring frozen samples back to the university in Los Angeles, where I spend many months analyzing them. For every hour we spent collecting, we spend several thinking and analyzing what we've collected. We also spend time running computer models and discussing ideas with teams of researchers. I don't do as much planning as I used to in terms of the organizational details that mounting an Antarctic expedition requires. I used to enjoy this more, but now I let the younger graduate students get involved with it since they still find it exciting. I really love diving and collecting samples. The novelty of discovery is very exciting. So is brainstorming–having informed discussions in a relaxed atmosphere and trying to come to a consensus and figure things out.

AMNH: How did you end up studying the adaptations of marine organisms in Antarctica?

Donal: My parents fostered my interests by buying me books and watching television documentaries about marine biology. I tried lots of thing outside of the classroom, and I built on my experiences. Most of them have proved useful in some meaningful way. My advice to kids is, don't stay at home. Try new things, meet new people, and explore things that interest you. That's the best preparation you can get.

AMNH: When did you get interested in marine biology in particular?

Donal: I took a summer job before college packaging frozen peas. While I was there, I started to think about where food to feed humanity would come from in the future. At the time, one third of all of the food in the world already came from the oceans, and people were saying that these fish supplies were in danger of being overfished. The idea of farming on the bottom of the ocean piqued my interest. The next summer I worked on a fishing trawler as a deckhand for three months. I got incredible sea-going experience–which proved useful when I was the chief scientist of a multimillion-dollar ship that discovered the Titanic.

AMNH: You really found your inspiration–what do you think it was about formal schooling that didn't interest you?

Donal: I was a typical kid, much more interested in playing soccer with buddies than doing extra work. Even in college, I wasn't as excited as I thought I needed to be. Then something exciting did happen: my freshman year in college, I started hanging around and volunteering in the laboratories where the graduate students were doing their research. That introduced me to a whole new world of what science is about: solving problems, discussing new ideas. I was turned off to the classroom, where it's mostly memorization and exams. But seeing what these researchers were doing and how much they knew gave me a reason to apply myself to my studies, in math, organic chemistry, and other important subjects. The next summer I took a job in a research lab, which I enjoyed, and when I returned to school that year I was absolutely committed to marine biology. In the end, I was drawn to my work and to Antarctica by the process of discovery. Students who maybe aren't that interested in homework should know that successful people weren't necessarily great students. I think students who think they're interested in science should work in a professional scientific setting as soon as they can, just to see what it's like. It's very different from school. There are lots of programs.

More About This Resource...

This in-depth profile of a marine biologist takes a look at the first explorers of the Antarctic and the challenges they faced. In the Q&A profile, which appears as both a Web article and a printable PDF, Donal Manahan answers more than 15 questions, including:

What were early theories about what Antarctica was like?

How did the early explorers communicate with the outside world?

Why did it take so long to find Antarctica?

When were huskies last used?

What problems did they encounter along the way?

Whom do you admire most among the Antarctic explorers?

Completion Time

Less than 1 period

Teacher Tip

Supplement a study of Antarctica or early explorers with an activity drawn from this essay.

Ask students to brainstorm a list of differences between today's explorers and the early explorers of Antarctica.

Send students to this online article, or print copies of the essay for them to read.

Have them revise and expand their list of differences based on what they learned in this article.